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Canker Sores: What are they and how to get rid of them?

Author: Ahmed Abbas

If your gums sting while you’re eating and drinking, you may have a canker sore! Canker sores are clinically called Aphthous Ulcers, and will likely leave after a week or so (Scishow, 2017). However, there are ways to prevent them from happening in the first place, reduce the pain if they do appear and possibly increase the speed of healing.

What are canker sores? What causes them? Canker sores are abrasions inside the mouth, caused by things that irritate the gums such as dentures, braces, spicy or acidic foods (Mayo Clinic, 2018). Hormones also can play a role. Studies have shown that stress can lead to more Canker sores due to inflammatory hormones (Preeti et al, 2011). Nutrition can also affect your risk of canker sores, as deficiencies in iron and vitamin B12 can thin the protective layer in your gums, causing canker sores (Pontes et al., 2009).

Additionally, some unlucky folks may be more prone to Canker sores reappearing and develop a condition called recurrent aphthous ulcers (RAU) (Barrons, 2001). 85% of RAUs are classified as minor RAUs where 1-5 sores are present, and 10% are major RAUs where 7-10 sores are present concurrently (Hennessy, 2020). RAUs are best treated by a specialist in oral medicine using Levamisole to reduce ulcer frequency and duration in patients with minor RAU. Oral corticosteroids are reserved only for severe cases of RAU (Hennessy, 2020; Barrons, 2001).

How can canker sores be prevented? One method is to avoid eating spicy, citric and acidic foods. Another is to include nutritious foods that are rich in Vitamin B12, Zinc, Folic acid and Iron into your diet, such as green leafy vegetables, red meat, liver and beans (My Health Alberta, 2020). For people who have previously had canker sores, using a soft-bristled brush, trying not to chew and talk at the time, and chewing your food slowly can reduce your risk of developing canker sores (My Health Alberta, 2020).


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Antônio Rebelo Pontes, H. Conte Neto, N. Bechara Ferreira, K. Paiva Fonseca, F. Monteiro Vallinoto, G. Sirotheau Corrêa Pontes, Santos Pinto Jr F. (September, 2009) Oral Manifestations of Vitamin B12 Deficiency: A Case Report. Journal of the Canadian Dental Association, 75(7).

Bernard J. Hennessy. (May, 2020). Recurrent Aphthous Stomatitis. Retrieved from: oral-disorders/ recurrent-aphthous-stomatitis

Canker Sores. Mayo Clinic. Retrieved from: /canker-sore/diagnosis-treatment/drc-20370620

Healthwise, My Health Alberta. (October, 2020). Health information and tools - Canker sores. Retrieved from:

Preeti, L., Magesh, K., Rajkumar, K., & Karthik, R. (2011). Recurrent aphthous stomatitis. Journal of oral and maxillofacial pathology : JOMFP, 15(3), 252–256.Retrieved from:

Robert W. Barrons. (January, 2001). Treatment strategies for recurrent oral aphthous ulcers. Am J Health-Syst Pharm, 58.


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